**7.1 Rotation and mixture**

This method involves use of insecticides of one or different classes with different target sites or distinguishable mechanism of actions in rotation or in sequence. The hypothetical basis of this strategy is that if the resistance to a particular insecticide

is rare, then the use of multiple insecticides may decrease the chances of resistance to the least possible. This strategy should be allowed to run for prolonged periods of time so that there is no reversal of the effect [102]. Thus, annual rotation programmes are carried out extensively with the rotation of multiple classes of insecticides with different target of actions for vector populations. Usually, this practice is carried out during the growing season in agricultural practices. The rotation and mixture method of insecticide resistance may further be modified by using insecticide mosaics and combinations. This includes use of two different insecticides in two different areas thus lowering down the probability of development of resistance against one particular insecticide [103].

## **7.2 Bioinsecticides**

Insecticides create a huge bioburden due to their chemical nature and pose a threat to human health and environment. Hence, there is a need to replace insecticides with biologically friendlier methods, such as by using bioinsecticides such as bacterial and fungal species against insecticides. Following this approach, the production of bioinsecticide has gained momentum, but have yet not been put to common use due to their high production cost. There is also a need to more research regarding their use and reliability. Many species of *Bacillus* are used in agriculture and have showed effective results. Plant extracts such as nicotine, pyrethrum, and neem oils are also are also been increasingly used with the green revolution. Another promising biocontrol agent is *Androctonus australis* anti-insect toxin (AaIT), which targets the neurological system of the insect vectors. Thus, exploitation of certain characteristics of the naturally occurring organisms in nature may potentially lead to the development of useful biocontrol agents against vector populations.
